A 4-month, structured diet and exercise intervention lowered blood pressure in adults with resistant blood pressure, according to results from a randomized, clinical trial. The program also led to improvements in baroreflex sensitivity, heart rate variability, and flow-mediated dilation, compared with individuals who received only a single education session.
The intervention included instruction from a nutritionist on how to follow the Dietary Approaches to Stop Hypertension (DASH) diet, as well as restricting calories and sodium to less than 2,300 mg/day. It included weekly, 45-minute group counseling sessions, run by a clinical psychiatrist, focusing on eating behaviors. The exercise component included 30- to 45-minute sessions at 70%-85% of initial heart rate reserve, carried out three times per week at a cardiac rehabilitation facility.
“While some individuals can make the lifestyle changes on their own, a structured program of supervised exercise and dietary modification conducted by a multidisciplinary team of physicians, psychologists, nutritionists, and physical therapists/exercise physiologists found in cardiac rehabilitation programs throughout the country is likely to be more effective. There are many cardiac rehabilitation programs throughout the country that are accessible to most patients,” said lead author James Blumenthal, PhD, the J.P. Gibbons Professor in Psychiatry and Behavioral Sciences at Duke University, Durham, N.C.
The study, called Treating Resistant Hypertension Using Lifestyle Modification to Promote Health (TRIUMPH), was published in Circulation. It is one of few that have examined lifestyle interventions in resistant hypertension, defined as systolic blood pressure ≥ 130 mm Hg or diastolic blood pressure ≥ 80 mm Hg after adherence to three or more optimally-dosed antihypertensive medications of three different classes, including one diuretic.
Dr. Bryan Williams
“This is a nice study [that] emphasizes what we often forget: Lifestyle factors, especially salt intake, are important drivers of resistant hypertension. Our own studies have shown that this is predominantly a salt retaining state, and one would expect dietary salt restriction to be particularly effective in this group of patients and that is what this study showed,” said Bryan Williams, MD, who was asked to comment on the study. Dr. Williams is chair of medicine at University College London.
The results should also be reassuring to some who worried that exercise might lead to worsened blood pressure. “This study showed that in patients with resistant hypertension, though not out of control blood pressures, exercise was not only safe, but effective in lowering their blood pressure,” said Deepak L. Bhatt, MD, MPH, who was asked to comment. He is executive director of interventional cardiovascular programs at Brigham and Women’s Hospital, and professor of medicine at Harvard Medical School, both in Boston.
Dr. Deepak L. Bhatt
The new research isn’t unique. In August, researchers in Portugal and Brazil showed that a 12-week exercise-only intervention reduced 24-hour and daytime ambulatory systolic and diastolic blood pressure. The two studies communicate the same message. “Lifestyle changes can work for resistant hypertension. So, two independent, modest-sized studies with essentially the same, positive, actionable conclusion,” said Dr. Bhatt, adding that the next step should be a larger, multicenter trial.
In the new study, 90 patients were assigned to the diet and exercise intervention and 50 to the control group. They had a mean age of 63 years, and 48% were women. Participants attended 94% of DASH diet classes and 89% of exercise sessions, and both groups had excellent adherence to medications.
The treatment group had a greater reduction in clinic systolic BP (–12.5 versus –7.1 mm Hg; P = .005) and diastolic BP (–5.9 versus –3.7 mm Hg; P = .034), as well as 24-hour ambulatory systolic BP (–7.0 versus –0.3 mm Hg; P = .001). The treatment group also had more improvement in resting baroreflex sensitivity (2.3 versus –1.1 ms/mm Hg; P = .003), high-frequency heart rate variability (0.4 versus –0.2 ln ms2; P = .025, and flow-mediated dilation (0.3% versus –1.4%, P = .022). The two groups had similar outcomes with respect to pulse wave velocity and left ventricular mass.
“Results of the TRIUMPH study suggest that policymakers should consider resistant hypertension as a new indication for cardiac rehabilitation with appropriate coverage by governmental agencies and private insurers,” Dr. Blumenthal said.
“This is an important new, evidence-based intervention for resistant hypertension. It is safe and relatively inexpensive. It should now be something physicians routinely offer these patients. Hopefully in the future, insurers will cover cardiac rehabilitation for patients with resistant hypertension,” Dr. Bhatt said.
The study also pointed towards an effective approach for patients who may be unable to sustain lifestyle changes. “Of course, not every patient will be able to maintain a healthy diet and an exercise program on their own, thus a cardiac rehabilitation program can be an excellent way to increase the likelihood of successful lifestyle modification,” Dr. Bhatt said.
TRIUMPH was sponsored by grants from the National Heart, Lung, and Blood Institute. None of the authors had disclosures to report. Dr. Bhatt disclosed having financial relationships with more than 40 pharmaceutical companies. Dr. Williams reported having no relevant financial disclosures.